Light waves are which type of waves?

For electromagnetic waves,the phase difference between the $\vec{E}$ and $\vec{B}$ vectors (for the region far from the source) is......

The nature of electromagnetic waves is .......

An electromagnetic wave of frequency $\nu = 3.0\,MHz$ passes from vacuum into a dielectric medium with permittivity $\varepsilon = 4.0\varepsilon_0$. Then

Which of the following is incorrect about a plane electromagnetic wave?

$A$ plane electromagnetic wave is propagating along the direction $\frac{\hat{i}+\hat{j}}{\sqrt{2}},$ with its polarization along the direction $\hat{k}$. The correct form of the magnetic field of the wave would be (here $B_{0}$ is an appropriate constant)